We plan to continue investigating the properties and mechanism of action of liver microsomal cytochrome P-450. The various forms of P-450LM will be isolated and characterized by immunochemical properties, carbohydrate and lipid content, and substrate specificity. The amino acid sequences will also be determined in collaboration with Dr. Kerry T. Yasunobu of the Universty of Hawaii. Using these enzymes and purified NADPH-cytochrome P-450 reductase we plan to examine the detailed mechanisms of electron transfer and oxygen activation which lead to substrate hydroxylation. Stopped-flow spectrophotometric methods will be used in determining the the kinetics of these rections.